A woman smokes marijuana during the annual 4/20 marijuana rally on Parliament Hill in Ottawa, Ontario, Canada, April 20, 2017. (Photo by Chris Wattie/Reuters)

In this March 7, 1991 file photo, a U.S. Marine patrol walks across the charred oil landscape near a burning well during perimeter security patrol near Kuwait City. Twenty five years after the first U.S. Marines swept across the border into Kuwait in the 1991 Gulf War, American forces find themselves battling the extremist Islamic State group, born out of al-Qaida, in the splintered territories of Iraq and Syria. The Arab allies that joined the 1991 coalition are fighting their own conflicts both at home and abroad, as Iran vies for greater regional power following a nuclear deal with world powers. (Photo by John Gaps III/AP Photo)

A woman reacts as she poses with a man dressed up as the Star Wars character Chewbacca outside the Dolby Theatre, the site of the 88th Academy Awards in Hollywood, California February 26, 2016. (Photo by Adrees Latif/Reuters)

Children play on an abandoned car near a protest, which is against the dissolution of Yemen's parliament and the Shi'ite Muslim Houthi militia's tightening grip on power, in the southwestern city of Taiz, February 13, 2015. (Photo by Mohamed al-Sayaghi/Reuters)

Handout photo dated March 20, 2015 issued by Chester Zoo of lemurs looking at the eclipse over Chester Zoo. (Photo by Steve Rawlins/PA Wire/Chester Zoo)

In this Thursday, April 16, 2015 photo provided by Robert MacFarlane, a raccoon climbs up a skyscraper in downtown Toronto. Social media was abuzz Thursday with the photo of the raccoon peering from between the metallic rungs of a crane 58 stories high. (Photo by Robert MacFarlane)

Valery Bystritskii, 10, gets a fellow student into a lock at Bunny's Gym in July 2015 in Winchester, Tennessee. (Photo by Mike Saliba/Barcroft USA)

A human rainbow is created at a BASEOrlando coordinated event, “Orlando Strong Body Paint”, on Friday, June 17, 2016 in Orlando, Fl. The group created the rainbow, composed of volunteers numbering the same as that of the victims of the Pulse shooting, as a visual reminder of the amount of lives lost. (Photos by Amanda Voisard/The Washington Post)